Study: CO2 deters Asian carp
By Tim Bunton
Champaign, Ill. — A team of scientists continues to show that controlling invasive Asian carp can be as simple as mixing up a batch of soda water.
Well, it’s not quite as simple as that. But adding carbon dioxide gas to water seems to control the movement and behavior of invasive carp in the Great Lakes basin, according to the team’s recent study.
“This study demonstrates the ability of carbon dioxide to act as a non-physical barrier on a large scale,” said Cory Suski, of the University of Illinois. “Work on this topic to date has primarily been performed in small, laboratory studies, and so this work showed the potential for CO2 to be effective at larger scales more relevant to field applications.”
The study was supported by Illinois DNR through funds provided by the U.S. Environmental Protection Agency’s Great Lakes Restoration Initiative.
The UI is teaming with the U.S. Geological Survey to test the effectiveness of infusing water with recycled CO2 gas to discourage the movement of bighead and silver carp.
Both carp species avoided CO2-infused water in a research pond at the USGS Upper Midwest Environmental Sciences Center in La Crosse, Wis.
“These fish responses provide evidence that CO2 could be used as a tool to deter the movement of bighead and silver carp,” said Michael Donaldson, another UI researcher and the study’s lead author. “The results are encouraging because there is a need for additional methods to prevent the entry of Asian carp into the Great Lakes.”
The scientists gradually added light plumes of CO2 gas to one end of the USGS test pond. They monitored the behavior of individual bighead and silver carp, as well as the behavior of native fish species such as bigmouth buffalo, channel catfish, paddlefish, and yellow perch before, during, and after the addition of CO2.
Findings of the study include:
• Each fish species except for paddlefish avoided the areas of the pond with CO2-infused water.
• Certain bighead and silver carp movements slowed down after CO2 was injected.
• Bighead carp used a smaller area of the pond farthest from the injection sites after CO2 was added.
“Further tests are needed before CO2 can be used in Asian carp management,” says Jon Amberg, a USGS scientist and co-author of the study. “Understanding the effects of long-term, elevated CO2 exposure on fish and other organisms can help assess its risks to native species.”
The next step is to test the usefulness of CO2 gas in controlling bighead carp movement in a natural river.
“Carbon dioxide as a tool to deter the movement of invasive Bigheaded Carps” has been published in Transactions of the American Fisheries Society and is available online.